基于离子膜的高灵敏电容式柔性压力传感器

针对精确测量微小人体生理信号的需求,文章采用聚乙烯醇、氢氧化钾为材料,结合砂纸倒模技术,制作一种具有微结构复合离子膜介电层的高灵敏柔性电容式压力传感器。详细阐述传感器制作流程,表征离子膜的化学特性,分析并优化介电层材料配比及微结构尺寸,在对传感器静态和动态特性进行测试后将之应用于人指尖脉搏波测量。结果表明,基于离子膜微结构介电层的柔性电容式传感器具有高灵敏度 $ (8.29\ \mathrm{kPa}^{-1}) $和快速响应时间 $ (45\ \mathrm{ms}) $,将该传感器安装到手指夹具中,通过脉搏波测量系统即可实现对人指尖脉搏的精确测量。该研究为可穿戴医疗电子设备提供了一种新的选择。

In order to meet the needs of precise measurement of subtle human physiological signals, by adopting polyvinyl alcohol and potassium hydroxide as the materials, and combined with sandpaper reverse mold technology, this paper produces a kind of high sensitivity flexible capacitive pressure sensor with microstructured composite ionic membrane dielectric layer. The production process of the sensor is described, the chemical characteristics of the ionic membrane are characterized, and the dielectric layer material ratio and microstructure size are analyzed and optimized. Then, the static and dynamic characteristics of the sensor are tested, and the sensor is applied to the human fingertip pulse wave measurement. The results show that the sensor has high sensitivity ( $ 8.29\ kPa^{-1} $) and fast response time (45 ms). The sensor is installed in the finger clamp, and the pulse wave measurement system realizes the accurate measurement of the human fingertip pulse, which provides a new choice for the wearable medical electronic devices.